Accession Number:



Quiet, Special-Purpose Revolver (QSPR) Design Improvements

Descriptive Note:

Final rept. Jul-Oct 1969

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The LWL Tunnel Weapon was evaluated in the Republic of Viet Nam. The results of this evaluation indicated that the weapon system was well received primarily because the low firing noise permitted use of the weapon without giving away the users position. In addition to its tunnel exploration role, the weapon was used in ambush situations and in search and destroy operations. Because of this, the weapon is now designated the Quiet, Special-Purpose Revolver QSPR. The objectives of this program were to determine the causes of misfires and malfunctions of the Quiet, Special-Purpose Revolver and its associated low signature, multi-projectile ammunition to modify or redesign components to effect necessary corrections including testing of all components to assure reliability of corrective action and to modify weapons and fabricate ammunition for reliability testing by USALWL. A secondary or helper spring was added to the weapons mainspring that provided a 50 increase in firing pin energy and eliminated mainspring degradation. The ammunition was redesigned with fewer parts and the primer was repositioned and exposed at the base of the round for direct contact by the firing pin as in conventional ammunition. These design improvements resulted in not a single misfire throughout the development, assurance, and acceptance tests associated with this program. A series of firing tests were conducted by LWL to evaluate the reliability and effectiveness of the QSPR and ammunition.

Subject Categories:

  • Guns
  • Ballistics

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